A vehicle includes a pair of suspension apparatuses and a stabilizer at left and right front wheels. The suspension apparatuses are attached to the wheels, and absorbs or reduces shock transmitted from a road surface to a vehicle body via the wheels. The stabilizer inhibits positional deviations of the left and right wheels, and enhances roll stiffness of the vehicle body. Furthermore, the suspension apparatuses are linked to the stabilizer using stabilizer links.
A hollow pipe is used for the stabilizer for the purpose of reducing the weight of the vehicle (see Patent Literature 1).
FIG. 12 is a perspective view showing a conventional stabilizer.
The stabilizer 101 includes: torsion arm portions 101a; and a torsion bar portion 101b whose end portions the torsion arm portions 101a are respectively joined to.
Left and right end portions 101a1 of the stabilizer 101 are each formed into a flat plate shape by hot forging because the left and right end portions 101a1 are bolted to the respective stabilizer links.
Since the stabilizer 101 uses the hollow pipe, there is likelihood that the stabilizer 101 deteriorates due to rust and the like from both its outer side (from outside its outer surface) and its inner side (from inside its inner surface) over time. Particularly because it is difficult to apply surface treatment such as painting to the inside of the stabilizer 101, the inside of the stabilizer 101 rusts and corrodes when water enters the stabilizer 101. Accordingly, the durability of the stabilizer 101 is highly likely to decrease.
Against this background, it is desired that the end portions 101a1 be watertightly closed in order that no water enters the stabilizer 101 when the left and right end portions 101a1 of the stabilizer 101 are plastically deformed into the flat plate shape.